​Behind blue eyes: Alcoholism may be linked to eye color

Blue-eyed people might have a greater chance of becoming alcoholics, while people with dark eyes are more alcohol-resistant, US genetic researchers have learned.

Claimed to be the first
of its kind, the work of scientists at the University of Vermont
suggests a surprising link between the eye color and
susceptibility to alcoholism, as well as many other psychiatric
illnesses and behavioral problems.

The results of the research, conducted by doctoral student Arvis
Sulovari and assistant professor Dawei Li, were published in the July issue of the American
Journal of Medical Genetics, Neuropsychiatric Genetics.

“This suggests an intriguing possibility – that eye color can
be useful in the clinic for alcohol dependence diagnosis,”
Sulovari said in the press-release.

The study was conducted based on data from over 1,200 people and
concentrated mostly on European Americans, but it was originally
founded on a huge database of over 10,000 Americans, both of
European and African ancestry. A threefold analysis revealed
genetic variables that were common to both eye color
determination and alcohol overindulgence.

The strongest correlation was among blue-eyed individuals, but
all people with light-colored eyes (that is, green, grey and
brown in the center) turned out to be more alcohol dependent than
those with dark brown eyes.

However, according to Li, “we still don’t know the reason” and
more research, as well as replication are needed.

As a next step, the scientists wish to explore the links between
cultural background and genetic makeup. Li stressed that all the
genes studied “can only explain a small percentage of the
genetics part that has been suggested. A large number is still
missing, is still unknown.”

“What has fascinated me the most about this work has been
investigating the interface between statistics, informatics and
biology,” said Sulovari. “It’s an incredible opportunity
to study genomics in the context of complex human diseases.”